Auto merge of #11930 - nox:die-util-die, r=SimonSapin

Remove some util stuff

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components/layout/construct.rs

@@ -30,6 +30,7 @@ use fragment::{InlineBlockFragmentInfo, SpecificFragmentInfo, UnscannedTextFragm
 use gfx::display_list::OpaqueNode;
 use inline::{FIRST_FRAGMENT_OF_ELEMENT, InlineFlow, InlineFragmentNodeFlags};
 use inline::{InlineFragmentNodeInfo, LAST_FRAGMENT_OF_ELEMENT};
+use linked_list::prepend_from;
 use list_item::{ListItemFlow, ListStyleTypeContent};
 use multicol::{MulticolFlow, MulticolColumnFlow};
 use parallel;
@@ -57,7 +58,6 @@ use table_wrapper::TableWrapperFlow;
 use text::TextRunScanner;
 use traversal::PostorderNodeMutTraversal;
 use url::Url;
-use util::linked_list;
 use util::opts;
 use wrapper::{TextContent, ThreadSafeLayoutNodeHelpers};
 
@@ -1805,8 +1805,7 @@ pub fn strip_ignorable_whitespace_from_start(this: &mut LinkedList<Fragment>) {
             }
         }
     }
-    linked_list::prepend_from(this,
-                              &mut leading_fragments_consisting_of_solely_bidi_control_characters);
+    prepend_from(this, &mut leading_fragments_consisting_of_solely_bidi_control_characters);
 }
 
 /// Strips ignorable whitespace from the end of a list of fragments.

components/layout/lib.rs

@@ -75,6 +75,7 @@ mod fragment;
 mod generated_content;
 pub mod incremental;
 mod inline;
+mod linked_list;
 mod list_item;
 mod model;
 mod multicol;

components/layout/linked_list.rs

@@ -0,0 +1,21 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+//! Utility functions for doubly-linked lists.
+
+use std::collections::LinkedList;
+use std::mem;
+
+/// Splits the head off a list in O(1) time, and returns the head.
+pub fn split_off_head<T>(list: &mut LinkedList<T>) -> LinkedList<T> {
+    let tail = list.split_off(1);
+    mem::replace(list, tail)
+}
+
+/// Prepends the items in the other list to this one, leaving the other list empty.
+#[inline]
+pub fn prepend_from<T>(this: &mut LinkedList<T>, other: &mut LinkedList<T>) {
+    other.append(this);
+    mem::swap(this, other);
+}

components/layout/text.rs

@@ -16,6 +16,7 @@ use gfx::text::glyph::ByteIndex;
 use gfx::text::text_run::TextRun;
 use gfx::text::util::{self, CompressionMode};
 use inline::{FIRST_FRAGMENT_OF_ELEMENT, InlineFragments, LAST_FRAGMENT_OF_ELEMENT};
+use linked_list::split_off_head;
 use range::Range;
 use std::borrow::ToOwned;
 use std::collections::LinkedList;
@@ -28,7 +29,6 @@ use style::properties::style_structs::ServoFont;
 use style::properties::{ComputedValues, ServoComputedValues};
 use unicode_bidi::{is_rtl, process_text};
 use unicode_script::{get_script, Script};
-use util::linked_list::split_off_head;
 
 /// Returns the concatenated text of a list of unscanned text fragments.
 fn text(fragments: &LinkedList<Fragment>) -> String {